How WIBA UK has assisted manufacturing firm in PPE production

WIBA UK technology has been helping ISO 13485 qualified injection moulder Thornbury Manufacturing Limited (TML) produce COVID-fighting PPE equipment. 

Plymouth-based TML’s medical and healthcare work has been steadily expanding to the point where it now comprises some 44% of total business and its ISO 13485 qualification (2016) was renewed some two years ago. 

Fast responses were needed in the early days of the pandemic and a significant order - via UK Government sources - came in for a new design of face shield; design-for-manufacture and production services were urgently needed. 

Both TML’s material supplier, (Distrupol) and its toolmaker (Mouldtech Solutions Paignton) all put their shoulders to the wheel.

TML’s founding experiences on the automotive supply-side came into play in terms of the need for extensive production and process validations, CAP (dimensional) studies and ongoing inspections and other protocols for the new item. 

TML founder and managing director, Dick Walsh, said: “The timeline for tools for this emergency was set at just 21 days. The material used to make the tools was P20 steel, on the soft side but good enough for our purposes as we were moulding a medical grade of polypropylene.

“Simon Clegg at our material partner, Distrupol, fast-tracked the mould flow software operations in order to highlight the best gate size and position, the fill pattern and fill times, cooling and cycle times, all of which proved to be very accurate at the first tool trial. Production there began on time with customer approval on day 21.”

Walsh recalls that six workstations were then set up. Full work instructions and operator training were then achieved within a couple of days. The first 5,000 sets of Face Shield packs were packed in four working days.

Walsh points out that the medical validation process is a necessary and complex part of the whole order. 

“All of our medical parts have to go through a mould tool verification process which include the following: Signature Identification; Installation Qualification; Visual Mould Tool Inspection; Test and Reference measuring Instruments; Installation and Start up; Auxiliaries and Ancillaries; Operational Qualification;Process Optimisation; Shrinkage Study; Process Window/ DOE; First Article Inspection; Dimensional Qualification/Capability.

“The most time-consuming part of the medical verification consists of the capability studies. This involves measuring various numbers of components that have been produced during three three-hour production runs. Normally we measure up to 125 parts on key dimensions with an acceptance criteria of CPK 1.66.

“Having carried over 50 of these medical validations we have found that the repeatability of the new Wittmann Battenfeld Machines are so good that any variation whatsoever on part dimension can be attributed to operator measuring error rather than machine variation.”

TML was able to validate and mould key items and deploy the six workstations to assemble the face shields, and to then sanitise and double bag them for despatch.

In all TML’s manufacturing, WIBA UK machines and ancillaries have been a constant - whether the workhorses of vertical injection moulding machines or the two new SmartPower production cells. Reliability and production repeatability have been key areas here. 

The company employs some 26 people operating on a site footprint of nearly 20,000 sq feet. A prompt and ready delivery service, coupled with machine reliability has been rewarded over the years with repeat business and support for TML’s continuing advances into the medical sector. 

Investment in new Battenfeld injection moulding machinery and other equipment has helped TML to raise its production volumes in recent months. 

Walsh added: ‘We value our partnership with Wittmann Battenfeld UK. Our customers and clients expect continuous and fault free engineering and production from TML – and these are the qualities that we also find in our growing fleet of Battenfeld injection moulding machines.

“The overall performance of our Wittmann Battenfeld range of machines is extremely high, low maintenance and problem free. When we do need some help the service from WIBA UK is first class.”